Balloon catheters are commonly used in angioplasty procedures to expand vessels in the body, for example, blood vessels that are narrowed due to the deposition of plaque during arteriosclerosis. Some balloon catheters have a slidable sheath over the balloon to adjust the length of the balloon that is inflated. In many angioplasty procedures, the balloon or a portion thereof is inflated and deflated multiple times, depending on the size or number of regions in the vessel that need to be expanded. Thus, the sheath can be partially retracted multiple times during a single procedure, corresponding to each time the balloon is expanded. Balloon catheters typically have a flexible tip located at the distal end of the sheath to prevent damage to the vessel during insertion of the catheter, for example, over a guide wire.
In some procedures, the balloon or a portion thereof is passed through the flexible tip prior to inflation. The flexible tip flares out in the distal direction as the balloon is inflated. Thus, the flexible tip can be permanently deformed during expansion and deflation of the balloon. The deformed shape of the tip may cause damage to the vessel wall when the sheath is advanced in or retracted from the vessel, and may also make it more difficult to retract the sheath into a guide catheter. The present disclosure provides a solution to this problem by providing a flexible tip that returns to its original shape after multiple balloon expansions.